Design and Construction of the Plugged-in ~(22)Na Based Slow Positron Beam Facility

The Beijing intense slow positron beam facility has restricted running time of the BEPC-LINAC designed for BES and BSRF operation, We have therefore designed and constructed the plugged-in 22Na based slow positron beam section in the Beijing intense slow positron beam line with which we can supply continuous slow positron beam for debugging of newly-built positron annihilation measurement systems and saving running time of the Beijing intense slow positron beam. The plugged-in 22Na based slow positron beam section includes positron source(22Na), positron moderator, E×B slow positron energy filter, multilevel electrostatic acceleration tube, radioprotection, magnetic transport system and vacuum system, etc. The new slow positron beam line will be running on April, 2006.